Rotational lighting system

ABSTRACT

A rotational lighting system comprising at least one lighting fixture suspended so as to be freely rotatable between its ends from a horizontal support. A means for suspending the lighting fixture comprises rigid electric current-conducting elements having a support means at one end so designed as to not only support the fixture but to conduct electric current therethrough from said elements to a light on the fixture. Additional lighting fixtures and/or dummy fixtures similarly suspended in series with one another but out of axial alignment may also be provided so that the lights of each fixture will each generate light beams along different and random paths as each fixture freely rotates about its own suspension means.

United States Patent Grebinar Aug. 7, 1973 l ROTATIONAL LIGHTING SYSTEM Primary ExaminerRichard C. Queisser [76] Inventor: Paul D. Grebinar, 10 Station Square, Assistant Exammer Damel Yas'ch Forest Hills NY. 375 Att0rneyWatson, Cole, Grmdle & Watson [22] Filed: Aug. 18, 1971 57 ABSTRACT Appl. No.: 172,738

A rotational lighting system comprising at least one lighting fixture suspended so as to be freely rotatable between its ends from a horizontal support. A means [52]- U.S. Cl. 240/52 R, 240/3, 240/73 R 51 Int. Cl. F21v 21/03 F21p 5/00 Suspendmg l fixture complses else [58] Field of Search 240/l0 1 3 49 trlc current-conducting elements having a support means at one end so designed as to not only support the 240/9 52 73 272/8 40/40 128 fixture but to conduct electric current thcrethrough [56] References Cited from said elements to a light on the fixture. Additional lighting fixtures and/or dummy fixtures similarly sus- UNITED STATES PATENTS pended in series with one another but out of axial alignl,960,534 5/1932 ment may also be provided so that the lights of each fix- 1'3l41966 9/1919 ture will each generate light beams along different and random paths as each fixture freely rotates about its 3:290:8l7 12/1966 Kravath 40/39 x suspens'on means 12 Claims, 9 Drawing Figures O H A 3 l0 A l )5 1 M I t Patented Aug. 7, 1973 3,751,654

3 Sheets-Sheet 1 P401 5. 6655/A/4Z Zwfsw, @Q WMfMM ROTATIONAL LIGHTING SYSTEM This invention relates generally to a lighting system capable of continuous rotation and more particularly to such a system including one or more lighting fixture and one or more fixtures having no lights, if desired, each of which is interconnected and suspended in series and each of which is capable of independent rotation so as to thereby describe random paths of light during rotation of the lighting fixtures.

In the various known prior art devices wherein elongated lighting fixtures are supported and suspended between their ends for some purpose, such fixtures, of the electrical type, are incapable of rotation about their support axes in excess of 360 without entangling their electrical cords. For this reason, most prior art suspended lighting fixtures could not be interconnected and suspended in series. Also, most of the counterbalanced-type fixtures are designed to facilitate vertical movement of the lamp whereas the assembly in accordance with the present invention is arranged and designed for an entirely different purpose, as will be seen from the description hereinafter. Also, most of the prior art counterbalanced-type light fixtures are designed to optimize the lighting in a specific area which lies in a larger but finite area as compared to that of the present invention wherein its basic object is to continuously vary the lighting area in a random fashion with the use of a plurality of suspended lighting fixtures, or to vary the lighting area in a fixed fashion with the use of a single suspended lighting fixture, and thus illuminate objects in an aesthetically pleasing way.

Another object of the present invention is to provide a rotational lighting system which is dynamic and which has a specifically designedlighting fixture or fixtures capable of continuous, independent rotation, thereby generating beams of light along a circular path, if one such fixture is used, and generating beams of lighttending to travel in random paths so as to produce a wide array of light paths.

Another object of this invention is to provide such a system wherein each of the systems fixtures is suspended in a counterbalanced manner from and through one another so as to be connected in series, each of such fixtures being freely rotatable independent of one another and each being suspended about means not coaxial with one another so that, upon rotation of each fixture about its own suspension means, as well as about the suspension means of the other fixtures from and through which it is suspended, a completely random light path is thereby generated.

A still further object of this invention is to provide a system wherein fixtures having no lights may be also similarly suspended and interconnected in series with the serially interconnected light fixtures so as to generate different and even more varied random paths of light in an interesting and aesthetically pleasing way.

A still further object of the present invention is to provide such a system wherein each of the fixtures is suspended by means of rigid elongated suspension tubes serving also as electric current conductors, a support means mounted at one end of the tubes including contact means for conducting the current from the current-conducting tubes to the fixture lamps, and fin plates on each fixture to facilitate easy independent rotation during air current movement.

Other objects, advantages, and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a schematic perspective showing of the rotational lighting system in accordance with the present invention as it is generally arranged suspended from a ceiling wall;

FIG. 2 is a side elevational view of three interconnected lighting fixtures suspended electrically in series from one another and from a ceiling wall;

FIG. 3 is an elevational view in part showing a typical fin plate used for each of the fixtures;

FIG. 4 is an elevational view of the rotary connector assembly for each fixture;

FIG. 5 is a vertical sectional view of the connector assembly taken substantially along the line 5 5 of FIG. 4;

FIG. 6 is a sectional view of the connector assembly suspension means taken substantially along the line 6 6 of FIG. 4, and

FIGS. 7a, 7b and 7c are, respectively, schematic showings of different configurations made possible with the rotational lighting system fixtures in accordance with the present invention.

Turning now to the drawings wherein like reference characters refer to like and corresponding parts throughout the several views, there is shown, in FIGS.

.1 and 2, a typical arrangement of lighting fixtures in accordance with the present'invention electrically and structurally interconnected and suspended in series in a mobile-like fashion from a ceiling wall C. Since all of the lighting fixtures are identical in their construction, only one will be described in detail referring specifically to FIGS. 3 through 6 of thedrawings.

Each of the lighting fixtures 10 comprises a box-like beam member 11 having mounted at one end a fin plate 12 and at its opposite end a spotlight 13, or similar type of lamp, mounted in any conventional manner by such means as brackets 14 so as to permit the lamps to be adjusted about a horizontal axis.

It will be seen that fins 12 are provided for insuring adequate rotation of each fixture about its own suspension means, generally designated 15, during movement of the air currents in a room such as that shown in FIG.

Suspension means 15 includes an elongated, rigid conductor element or tube 16, which is hollow and preferably made of copper. Element 16 is covered by a sheath of insulation material 17about which an outer, hollow conductor element 18 is disposed which likewise comprises a rigid elongated copper tube so that together with copper tubing 16, electrical current may be conducted from a source (not shown) toward lamp 13 mounted on its respective lighting fixture. A protective sheath of insulation 19 is also disposed along the outside of outer tubing 18.

Near one end of the suspension means 115, a nonmetallic spherical pivot ball 21 is slidingly engaged about the outer insulation cover I9 and is held in place by means of a retainer ring 22, which has been pushed down over the pivot ball so as to wedge itself firmly along the outer periphery of the outer tubing 18. A nylon or other non-metallic washer 23 is disposed over one end of the inner tubing 16, as clearly shown in FIGS. 4 and 5, and another retainer ring 24 is thereafter clipped on in place so as to firmly rest against washer 23 and wedge itself into the outer periphery of the inner tubing 16. Accordingly, retainer rings 22 and 24 prevent any downward sliding of movement of either conductor element after the suspension means has been mounted in place.

It can be clearly seen in FIGS. 4 and 5 that an opening 25 is provided in the ceiling wall C which is of a slightly smaller diameter as compared to that of spherical pivot ball 21, thereby preventing the suspension means from dropping down through the opening while, at the same time, permitting the lighting fixture to slightly pivot along the edge of opening 25, if necessary.

A means for both supporting fixture beam 11 as well as for conducting electric current from the lower tubes to the lamp 13 is mounted at the lower end of suspension means 15, as clearly seen in FIGS. 4 and 5. A solid semi-cylindrical, non-metallic pivot element 26, having a central opening 26a therein of a greater diameter than the outer diameter ofinsulation 19, is disposed out of contact about insulation 19. This pivot element engages each of a pair of arcuate cut-out portions 27 (only one shown in FIG. 5) of a channel-shaped retainer bar 28 held in place along the under surface of a portion of beam 11 by means of screws 29.

The support means further comprises an annular non-metallic contact block 30 in which an electrical contact element 32, in the form of a metal pin, is horizontally disposed. A similar annular non-metallic contact block 31 is also provided in which another electrical contact element 33, also in the form of a metal pin, is horizontally disposed. An annular non-metallic spacer block 34 is located between the contact blocks bushing plates 35, resting on the top surface of each contact block, are provided for bushings 36. Both the bushing plates and bushings are, ofcourse, nonmetallic, with each of the bushings 36 engaging outer conductor element 18, as clearly shown in FIG. 5.

A ball-bearing member 38 also surrounds the outer conductor element, bears against the underside of contact block 30, and is held in place along with the remaining interconnected elements of the support means by means of retainer ring 38, which is simply seated against the underside of ball-bearing member 37 so as to wedge itself along the periphery of the outer conductor element. The contact blocks 30, 31 and the spacer block 34 are all interconnected by means of elongated screws 39 located at diagonally opposed corners of the blocks.

Each of the contact pins 32,33 are held, respectively, against the outer and inner conductor elements 18,16 by means of copper spring plates 41,42. Each spring plate is, in turn, held in place by means of metal screws 43 threadedly engaged with spacer block 34. Also, a conductor wire 44 is secured to one of the metal screws 43 and another conductor wire 45 is secured to the other metal screw to thereby electrically interconnect the lamp 13 with the power source (not shown) through conductor wires 44',45', contact pins 32,33 and plates 41,42.

It can be therefore seen that, as the beam 11 rotates along with its support means during the movement of air currents against fin plate 12 within the room, support means 15 will remain stationary so that each of the spring-loaded contact elements 32,33 moves along the periphery of the outer and inner conductor elements in continuous contacting relationship therewith. Such an arrangement therefore permits a rotational movement in excess of 360 in either direction since no entangling of electric wire cords will prevent such an almost indefinite rotational movement.

The topmost lighting fixture 10 is suspended from the ceiling in a manner hereinabove described, the suspension means 15 being so disposed along the length of beam 11 to permit a similarly designed and constructed lighting fixture 10 to be suspended from the fin plate end of the topmost fixture in counterbalancing relationship with lamp 13 on said topmost fixture. Furthermore, the support means 15 of the middle lighting fixture is so disposed along the length of its beam 11 that yet another lighting fixture 10 may be suspended from the fin end of the middle lighting fixture beam in counterbalancing relationship with the lamp 13 of the middle fixture. With such an arrangement, it can be seen that a mobile-like series of structurally and electrically interconnected lighting fixtures 10 are suspended from the ceiling wall C in a manner clearly shown in FIGS. 1 and of the drawings. Also, each of the lamps shown therein is electrically connected in series through the hollow beams 11 in any well-known manner. By such an arrangement, the system is rendered completely dynamic since each of the lighting fixtures is capable of independent rotation about its respective suspension means and about each of the lighting fixtures from which it is suspended since all three fixtures, in this case, rotate about different paths. If the system consists of only a single lighting fixture l0, rotation thereof about its support means will generate a circular path of light. Systems consisting of more than one lighting fixture will have the second and lower level fixtures generating light paths which tend to be random, these paths travelling, however, only within a specific area. Since each of the lighting fixtures 10, as shown in FIGS. 1 and 2, rotates independently about its suspension means, and since the suspension means of each fixture is not co-axial with another, it can be seen that completely random paths of light are traced by the middle and lowermost fixtures so that the various light beams will seldom be incident upon objects or persons beneath the lighting system from the same angle or light. It should be noted that the air currents relied upon for rotating each lighting fixture by means of its thin fin plate may arise from the heating, ventilation or air conditioning ducts or the opening and closing of doors and windows. Air currents may also be planned, i.e., fans or blowers may be aimed directly at the system.

Many different arrangements of lighting fixtures are possible within the scope of the present invention. Moreover, dummy lighting fixtures, i.e., fixtures having no lamps may also be made part of the rotational lighting system and arranged in any variety of configurations. Several exemplary configurations are shown in FIGS. 7a, 7b and 7c. In FIG. 7a, a dummy fixture 50 is shown suspended from a ceiling. Each of the dummy fixtures 50 comprises an elongated box beam 11, similar to that used for the lighting fixture, and having mounted at one end thereof a thin fin plate 12, also similar to the fin plate used for the lighting fixtures. The suspension means 15, as well as the support means thereon for supporting the hollow beams of the fixtures 50, are identical to those described above for the lighting fixtures 10. However, since no lamps are provided for dummy fixtures 50, the electrical wiring is simply fed through the dummy beams 11 to interconnect with a lower suspension means 115 so that the lamp or lamps of the particular arrangement may be electrically connected in series with the power source. In such manner, the dummy fixture 50 may likewise freely and independently rotate about its suspension means 15 as the air currents within the room move against its fin plate 12 in a manner similar to that for the lighting fixtures 10.

In FIG. 7a, the suspension means 15 for fixture 50 is disposed along the length of its beam 111 in such a manner as to permit lighting fixture 10 to be suspended from the free end of fixture 50 in counterbalancing relationship therewith. As before, the suspension means for the two fixtures are not co-axial so that with a rotation of the lighting fixture 10 about its support means 15, a random path of light from lamp 13 will be generated since the dummy fixture 50 is also capable of rotating independently about its own suspension means 15.

In FIG. 7b, it can be seen that a dummy fixture 50 is first suspended from a ceiling wall from which one lighting fixture 10 is suspended at its fin plate end while yet another lighting fixture 10 is suspended from its free end. Additionally, a third lighting fixture 10 is suspended between the ends of the third lowest fixture, as clearly seen in the drawing.

In FIG. 7c, a lighting fixture 10 is suspended directly from the ceiling, a dummy fixture 50 is suspended from the fin plate end of the lighting fixture, another lighting fixture 10 is suspended from thefree end of the dummy fixture, and yet anotherlighting fixture 10 is suspended from the fin plate end of the dummy fixture. It can be therefore seen that with such an arrangement of lighting fixtures and dummy fixtures, a completely random and unpredictable series of light patterns is generated by the various lamps as each of the fixtures moves independently about its own suspension means and about the suspension means of the fixtures from and through which it is suspended.

From the foregoing, it can be seen that the construction and arrangement of the rotational lighting system herein is basically quite simple. The suspension means 15 is easily attached to the ceiling so that the electrical connections from the power source are completely concealed, the suspension means blends completely into the decor of the room and is, moreover, structurally sound enough to support the'weight of the system as well as to conduct electric current to each of the lamps. The lamps of each of the lighting fixtures of the various suspended arrangements are electrically connected in series simply through the box means of the various fixtures and the various conductor elements of the suspension means whether or not the fixture be a lighting or a'dummy one.

The support means for the beam of each fixture is secured to the suspension means and electrically interconnects the conductor elements thereof with the lamp in a manner permitting free rotation of the fixture with a minimum amount of friction and a minimum amount of heat build-up while conducting the electric current therethrough. The fixture is capable of pivotong at both ends of the suspension means and the construction of the assembly permits little maintenance whilebeing completely reliable.

The lamp fixtures may be provided with any variety of lamps spot, medium flood or flood types, which are pivotable so as to be capable of being directed at different areas. Moreover, various lighting accessories, such as filters and louvers of the lightweight type, may be secured to any of the fixtures. By reason of such simple construction, rapid replacement of the lamps is facilitated, along with rapid change of the accessories in the interest of maintaining an aesthetically pleasing appearance.

The wiring of each fixture is completely concealed, and by reason of the type of suspension means used, the fixture is structurally supported and is structurally sound enough to sustain all static and dynamic loads it is subjected to. Moreover, the simple fin plate provides a relatively large surface for the purpose of catching air currents, the fins also being replaceable, if desired, with smaller or larger ones so as to decrease or increase the surface area thereof.

The operation of the present rotational lighting system is also of a simple nature. Electrical power goes into the system through the suspension means and is fed into the various light fixtures via the support means thereof. Each fixture is free to rotate about its own sus pension means with the various air currents in the room causing the fixtures to independently rotate at a certain speed of rotation depending on the relativevelocity of the air currents.

The path of the light being generated by movement of the uppermost lamp fixture is a circle. The paths of the lower elements are, however, more complex. In fact, the lower down the fixture, the greater the possibility of random movement. The light beam paths generated by the second and subsequent fixtures are degenerate circles or series of continued loops. These non-repetitive patterns are caused by the second fixture rotating at a different speed, as compared to the fixture from which it is supported. The net effect of the difference in rotational speeds is that the light beam of the second fixture travels in various paths, and the exact location of the light beam at any time, within the area to which it is restricted, is a matter of probability which will be a function of the air current speed, direction and duration.

The path of the lighting generated by third and subsequent light fixtures, if provided, is essentially of the same nature as those generated by the second fixture except that the third fixture '5 light beam path will have an even more degree of freedom; that is, the third fixture may rotate or be rotated about three interconnected lamp fixtures.

It should be noted that the maximum dimensions of the beam of light as it reaches the floor will be the function of the type of lamp (e.g., spot or flood), the height of the lamp set off the floor, and the angle at which the fixture is set. If the air currents are of a constant speed and direction and are continuous, then the light path movement of the assembly will tend to be periodic.

The possible uses for the instant rotational lighting system are numerous. A few typical applications might be museums, displays, discotheques, night clubs, lobbies, airline terminals, waiting areas, private homes and apartments with high ceilings, and in photographers studios.

Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

l. A rotation lighting system comprising at least one light fixture suspended between its ends from a first support that is connected to a surface, said fixture comprising an balanced elongated beam having a vertical fin plate rigidly mounted thereon to effect rotation of said beam in response to physical conditions, and a light element mounted near one end thereof, means for structurally and electrically interconnecting said beam with said first support comprising a rigid elongated suspension means and a means rotatably mounted at one end of said suspension means for supporting said beam so that said beam, together with said rotatable support means, is freely rotatable about said suspension means, said suspension means comprising conductor elements for conducting electric current, and said rotatable support means having contact elements in slidable contacting engagement with said conductor elements to both permit a free rotation of said rotatable support means and of said supported beam about said suspension means and to conduct electric current to said light element from said conductor elements.

2. The rotational lighting system, according to claim 1, wherein a plurality of said light fixtures are provided, each being suspended between their respective ends from said one light fixture, and each being suspended from one another.

3. The rotational lighting system, according to claim 2, wherein said conductor elements of each said suspension means comprise-a pair of elongated tubular elements disposed one within the other, insulation means disposed between said elements and about the outer one thereof.

4. The rotational lighting system, according to claim 3, wherein said electrical contact elements of each said support means are in contacting engagement, respectively, with each of said tubular elements of each said suspension means and are each slidable thereon upon rotation of said each fixture about its respective suspension means.

5. The rotational lighting system, according to claim 4, wherein each said support means further includes a pivot element in contact with the underside ofa portion of each said beam.

6. The rotational lighting system, according to claim 5, wherein said fin plate and said light element are mounted on each of their respective beams in counterbalancing relationship thereto on opposite sides of their respective suspension means.

7. The rotational lighting system, according to claim 1, wherein said conductor elements comprise a pair of elongated tubular elements disposed one within the other, insulation means disposed between said elements and about the outer one thereof.

8. The rotational lightingsystem, according to claim 7, wherein said electrical contact elements are each in contacting engagement with respective ones of said tubular elements and are each slidable thereon upon rotation of said fixture about said suspension means.

9. The rotational lighting system, according to claim 8, wherein said support means further includes a pivot element in contact with the underside of a portion of said beam.

10. The rotational lighting system, according to claim 9, wherein said fin plate and said light element are each mounted on said beam in counterbalancing relationship thereto on opposite sides of said suspension means.

11. The rotational lighting system, according to claim 1, further including a second fixture suspended between its ends from said one light fixture, said second fixture comprising a second elongated beam having a second vertical fin plate mounted thereon, means for suspending said second beam from said one light fixture comprising a second rigid, elongated suspension means and a means rotatably mounted at one end of said suspension means for supporting said second beam so that said second fixture, together with its support means, is freely rotatable about its suspension means, each of said suspension means being disposed at such a location along the length of its respective beam that said fixtures will each be counterbalanced about its respective suspension means.

12. A rotational light system comprising a plurality of light fixtures, one of said fixtures being suspended between its ends from a horizontal wall and the remainder of said fixtures each being suspended between their respective ends from said one of said fixtures and by one another in series, each of said fixtures comprising an elongated beam having a vertical fin plate mounted thereon and a light element mounted near one end thereof, means for suspending each of said light fixtures comprising a rigid, elongated connector assembly and means including a conductor assembly rotatably mounted near one end of its respective connector assembly for supporting each of said beams so that each of said fixtures, together with its respective support means, is freely rotatable about its respective connector assembly, each said conductor assembly comprising conductor elements for conducting electric current, each said support means having contact elements said conductor assembly in slidable contacting engagement with its respective conductor elements so as to both permit a free rotation of said support means and so as to conduct electric current to its respective light element from its respective conductor elements, each of said suspension means being disposed at such a location along the length of its respective beam that each of said fixtures will be counterbalanced about its respective suspension means.

* i t t i 

1. A rotation lighting system comprising at least one light fixture suspended between its ends from a first support that is connected to a surface, said fixture comprising an balanced elongated beam having a vertical fin plate rigidly mounted thereon to effect rotation of said beam in response to physical conditions, and a light element mounted near one end thereof, means for structurally and electrically interconnecting said beam with said first support comprising a rigid elongated suspension means and a means rotatably mounted at one end of said suspension means for supporting said beam so that said beam, together with said rotatable support means, is freely rotatable about said suspension means, said suspension means comprising conductor elements for conducting electric current, and said rotatable support means having contact elements in slidable contacting engagement with said conductor elements to both permit a free rotation of said rotatable support means and of said supported beam about said suspension means and to conduct electric current to said light element from said conductor elements.
 2. The rotational lighting system, according to claim 1, wherein a plurality of said light fixtures are provided, each being suspended between their respective ends from said one light fixture, and each being suspended from one another.
 3. The rotational lighting system, according to claim 2, wherein said conductor elements of each said suspension means comprise a pair of elongated tubular elements disposed one within the other, insulation means disposed between said elements and about the outer one thereof.
 4. The rotational lighting system, according to claim 3, wherein said electrical contact elements of each said support means are in contacting engagement, respectively, with each of said tubular elements of each said suspension means and are each slidable thereon upon rotation of said each fixture aboUt its respective suspension means.
 5. The rotational lighting system, according to claim 4, wherein each said support means further includes a pivot element in contact with the underside of a portion of each said beam.
 6. The rotational lighting system, according to claim 5, wherein said fin plate and said light element are mounted on each of their respective beams in counterbalancing relationship thereto on opposite sides of their respective suspension means.
 7. The rotational lighting system, according to claim 1, wherein said conductor elements comprise a pair of elongated tubular elements disposed one within the other, insulation means disposed between said elements and about the outer one thereof.
 8. The rotational lighting system, according to claim 7, wherein said electrical contact elements are each in contacting engagement with respective ones of said tubular elements and are each slidable thereon upon rotation of said fixture about said suspension means.
 9. The rotational lighting system, according to claim 8, wherein said support means further includes a pivot element in contact with the underside of a portion of said beam.
 10. The rotational lighting system, according to claim 9, wherein said fin plate and said light element are each mounted on said beam in counterbalancing relationship thereto on opposite sides of said suspension means.
 11. The rotational lighting system, according to claim 1, further including a second fixture suspended between its ends from said one light fixture, said second fixture comprising a second elongated beam having a second vertical fin plate mounted thereon, means for suspending said second beam from said one light fixture comprising a second rigid, elongated suspension means and a means rotatably mounted at one end of said suspension means for supporting said second beam so that said second fixture, together with its support means, is freely rotatable about its suspension means, each of said suspension means being disposed at such a location along the length of its respective beam that said fixtures will each be counterbalanced about its respective suspension means.
 12. A rotational light system comprising a plurality of light fixtures, one of said fixtures being suspended between its ends from a horizontal wall and the remainder of said fixtures each being suspended between their respective ends from said one of said fixtures and by one another in series, each of said fixtures comprising an elongated beam having a vertical fin plate mounted thereon and a light element mounted near one end thereof, means for suspending each of said light fixtures comprising a rigid, elongated connector assembly and means including a conductor assembly rotatably mounted near one end of its respective connector assembly for supporting each of said beams so that each of said fixtures, together with its respective support means, is freely rotatable about its respective connector assembly, each said conductor assembly comprising conductor elements for conducting electric current, each said support means having contact elements said conductor assembly in slidable contacting engagement with its respective conductor elements so as to both permit a free rotation of said support means and so as to conduct electric current to its respective light element from its respective conductor elements, each of said suspension means being disposed at such a location along the length of its respective beam that each of said fixtures will be counterbalanced about its respective suspension means. 